Antibacterial composition

ABSTRACT

Lotion compositions for applying topically to skin include a barrier-forming polymer mixture and an anti-microbial agent. The polymer dries on skin to form a barrier which prevents pathogens, solvents and petrochemicals from penetrating into the skin. The barrier is resistant to being washed off for at least several hours, during which time the antibacterial agent effectively kills a broad spectrum of bacteria within seconds after contact.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.08/671,148, filed Jun. 24, 1996, now abandoned.

FIELD OF THE INVENTION

The invention relates to compositions and methods for protecting skinand preventing carryover of biohazardous substances from one material toanother. In particular, the invention involves lotion compositions whichare applied on skin to form a protective polymer coating while alsobeing capable of rapidly killing a broad spectrum of microbialpathogens.

BACKGROUND OF THE INVENTION

There are many situations where people need to expose their hands topotentially hazardous materials including microorganisms, chemicals,etc., in connection with their work. A few examples of workers whomanually encounter biohazards in their jobs include restaurant workers,food processors in meat and poultry plants, health care professionalssuch as physicians, nurses, emergency medical technicians, police,prison guards, fire fighters, mechanics, etc. In the food service andprocessing industries, workers' hands frequently contact pathogenicorganisms which can be dangerous to the worker or to the recipients ofthe processed food. In the past several years the public has beenespecially aware of this problem with respect to the handling of meatand poultry due to severe illness caused by the bacteria E. coli andSalmonella.

Workers' hands also come into contact with hazardous chemicals such ascommercial solvents and petrochemicals which may damage the worker'sskin and/or be absorbed through the skin possibly carrying otherhazardous solutes and causing internal toxicity.

In coming up with a strategy for protecting people from manuallyencountered biohazards in the workplace, it is important to consider theneed to protect the worker as well as the need to protect the consumer.For example, the most common approach for protecting a worker's handsfrom biohazardous organisms or chemicals is to wear gloves. However,even if a glove material is capable of acting as a complete barrierprotecting the worker's hands, the gloves do not prevent carryover(cross contamination) of hazardous materials from one material toanother. A worker wearing gloves may work with hamburger one minute andmake a salad minutes later without changing gloves. This may result incarryover or cross-contamination of a hazardous substance or pathogenfrom one food to another. Accordingly, even if gloves protect theworker's skin, they do not adequately protect others who may be injuredfrom carryover of hazardous materials in the workplace.

Another problem with gloves is that they reduce the worker's dexterity.This causes some workers not to wear gloves even in situations wherethere are dangerous chemicals or pathogens in the work environment. Forexample, machinists and mechanics frequently have to manipulate devicesin small spaces or compartments where solvents and petrochemicals arepresent. The worker may not wear gloves in these situations because todo so would compromise the worker's agility or dexterity, thus slowingdown or preventing the worker from carrying out his work. Gloves alsosignificantly limit or prevent the worker from using his sense of touchwhich may be essential to the activity.

Accordingly, an important object of the present invention is to providean alternative to wearing gloves which protects the user's hands frombiohazardous materials while also preventing cross contamination.

A further object of the invention is to provide a lotion for use onhands which is capable of broad spectrum bactericidal and antiviralactivity within seconds of contact. The lotion should maintain itsanti-microbial efficacy for at least several hours after application tothe skin.

Another important object of the invention is to provide a polymer-basedbarrier on the skin which resists being washed-off and which preventsabsorption through the skin of hazardous chemicals and commercialsolvents.

Another goal of the invention is for the lotion's antibacterial andbarrier functions to be relatively insensitive to the pH of thehazardous material.

Still another object is for the lotion to be nontoxic to humans.

The lotion should have a useful shelf-life of at least about two years.During that time the solution/emulsion should remain homogenous withoutany precipitation or separation of phases. The lotion's anti-microbialefficacy must also be maintained during the shelf-life period.

SUMMARY OF THE INVENTION

The present invention provides a lotion for application to skin for thepurpose of protecting the skin from biohazardous materials such assolvents and petrochemicals which may damage the skin and/or be absorbedinto the skin along with potentially toxic solutes, and for the purposeof preventing cross contamination of potentially hazardous pathogenssuch as bacteria and viruses from one material to another. One formulaof the present invention includes a mixture of polyvinylpyrrolidone(PVP) and hydroxyethylcellulose (HEC) in an aqueous solution, and anantibacterial agent dispersed in the solution. In another formula of theinvention, the PVP and HEC polymer mixture is replaced by an aqueouscarbomer solution. After application to the skin, the polymer materialdries into a barrier film which resists being washed off and whichprevents a variety of different chemicals and pathogens from contactingor penetrating the skin. The antibacterial agent kills bacteria uponcontact or shortly thereafter. Different antibacterial agents are usedsuch as 2,4,4'-trichloro-2'hydroxydiphenylether ("triclosan") orchlorhexidine gluconate. The lotion may also include other materialssuch as antiviral agents, emulsifying agents, emulsion stabilizers,emollients, plasticizers, preservatives, aloe vera, glycerine andvitamin E.

The polymeric/antibacterial formulas of the present invention are uniqueand advantageous in their ability to provide a penetrant barrier whichresists being washed off while providing broad spectrum anti-microbialefficacy for at least four hours after the lotion is applied to theskin. During that time period, bacteria which comes into contact withthe antibacterial barrier is killed within seconds after contact.

Lotions of the present invention are typically produced by firstdispersing and dissolving the polymers in water. The solution is thenheated to approximately 75-80° C. In a second solution the emulsion,emollient and plasticizer components are mixed and heated to about75-80° C. The second solution is then added to the first solution andmixed while cooling to about 40° C. A third solution including theantibacterial agent is then mixed into the batch. The solution is mixedwhile cooling to 35° C. and then the preservative is added. Finally, ifnecessary, the pH is adjusted to about 6.5-7.0.

DESCRIPTION OF THE INVENTION

The invention provides a number of lotion formulas, each of which,fundamentally, includes a polymeric film-forming component and anantibacterial agent dispersed in the polymer material. The polymericcomponent must be selected and formulated so that after application onskin, it dries into a coating which is not easily washed or rubbed offand which serves as a barrier to prevent penetration of hazardoussolvents and/or petrochemicals into the skin. The barrier is effectivefor at least several hours after application. We have discovered atleast two different types of polymers which can be used for thispurpose. Examples of these polymer formulas are detailed below. Three ofthe examples described include a mixture of polyvinylpyrrolidone (PVP)and hydroxyethylcellulose (HEC). The PVP preferably has a molecularweight in the range of about 20,000-40,000 daltons and is provided inthe solution at a concentration of between approximately 0.10 to2.00-percent (w/w). The HEC is provided in the solution at approximately0.10 to 2.00-percent (w/w). In another formula, instead of using PVP andHEC, Carbopol™ 980 (an acrylic polymer) is used at a concentration ofbetween approximately 0.05 to 2.00-percent (w/w). There are manydifferent molecular weights available for these polymers, i.e., 12,000to 2,800,000. The molecular weights and concentrations of thesematerials are carefully selected, balanced and stabilized because toomuch will cause the barrier to disrupt and flake or roll off the skinwhile too little will provide an inadequate barrier.

Examples of four formulas of the present invention are given below,along with procedures for manufacturing the lotions. The percent figuresare in terms of weight/weight. Preferred suppliers for the materials arealso set forth. The first three formulas include PVP K-30 and HEC(Natrosol™ 250 HHR) as the film forming polymers. In the fourth formula,Carbopol™ 980 is used instead.

It turned out to be quite difficult to find a combination of polymersthat can fulfill each of the objectives of: (a) remaining homogeneous,while exhibiting a smooth luxurious lotion quality, without causing theantibacterial agent to precipitate or come out of solution, and (b) whenapplied to the skin, forming a continuous long-lasting, wash-offresistant barrier film that allows the anti-bacterial agent to remaineffective over an extended period of time. We discovered that thecombination of PVP with HEC satisfied these objectives far better thaneither ingredient without the other, or any other polymer combination wetried.

Another important component of the composition is an antibacterialagent. The agent must be dispersable and stable at an effectiveconcentration in solution with the polymer mixture and any othernecessary dispersing or emulsifying agents, etc. For example, oneantibacterial agent which is used in the present invention is2,4,4'-trichloro-2'-hydroxydiphenylether ("triclosan") at aconcentration of between about 0.10 to 2.00-percent (w/w). Anotherantibacterial agent used in the present invention is chlorhexidinegluconate at a concentration of between about 0.10 to 3.00-percent(w/w).

Another important ingredient of the present invention is an antiviralagent. For example, Carsonan™ N-9 at a concentration of about0.50-percent (w/w) may be included in the lotion. Carsonan™ N-9 isavailable from Lonza and is generically known as nonylphenol thoxylate.Nonylphenol thoxylate has been shown to be effective in killinghepatitis B and HIV viruses.

An emulsion stabilizer such as Crodocal™ C-95 provides skin emolliency.An emulsifying agent such as Lipomulse 165 is included in the formula toprovide skin conditioning. Lexol™ IPM, a myristic acid ester, is used asan emollient and plasticizer for the barrier film. A preservative suchas Germaben™ II-E is also used.

In some instances materials are referred to by the trade names ofpreferred suppliers. Information about preferred materials are providedbelow.

PVP K-30 is purchased from ISP.

Natrosol® 250 HHR, hydroxyethylcellulose from Hercules Inc., is anon-ionic water-soluble polymer which is initially provided as afree-granular powder.

Crodacol™ C-95 is cetyl alcohol available from Croda Inc.

Aloe vera powder 200XXX is purchased from Tri-K in the form of a finepowder.

Lexol IPM is obtained from Inolex Chemical Company. It is isopropylmyristate, an ester of isopropyl alcohol and myristic acid.

Vitamin E is purchased from Roche Vitamins and Fine Chemicals.

Chlorhexidine gluconate is obtained from Xtrium in a stock concentrationof about 20-percent (w/v). It is also known as 1,1'-hexamethylenebis5-(4-chlorophenyl)biguanide!digluconate.

Germaben® II-E is a liquid preservative available from SuttonLaboratories. It is a clear viscous liquid including 20-percentdiazolidinyl urea, 10-percent methylparaben, 10-percent propylparabenand 60-percent propylene glycol.

Versene™ XL100 is obtained from Dow Chemical Company. As provided, it is38-percent tetrasodium salt of ethylene-diaminetetra acetic acid,61-percent water and 1-percent sodium hydroxide.

Irgasan DP300 is a broad spectrum anti-microbial agent available fromCiba-Geigy Corporation. It is also known as2,4,4'-trichloro-2'-hydroxydiphenyl or5-chloro-2-(2,4-dichlorophenoxy)phenol or "triclosan."

Carsonon N-9 is nonylphenol thoxylate available from Lonza.

Carbopol® 980 is an acrylic polymer also known as carbomer or carboxypolyethylene available from B. F. Goodrich.

D.C. 200 fluid from Dow Corning is a clear, waterwhite dimethylpolysiloxane fluid.

Lipomulse™ 165 is available from Lipo Chemicals, Inc. It containsapproximately equal parts of glyceryl stearate and PEG-100 stearate.

EXAMPLE 1

    ______________________________________    Ingredient          Percent   Supplier    ______________________________________    Part A    Deionized Water     90.77     --    PVPK-30             0.25      ISP    Natrosol 250 HHR    0.195     Aqualon    Glycerin USP        1.25      Dow    Aloe Vera Powder 200XXX                        0.002     Tri-K    Part B    Crodacol C-95       0.20      Croda    Lipomulse 165       1.06      Lipo    Lexol IPM           0.15      Inolex    Part C    Deionized Water     4.0       --    Chlorhexidine Gluconate                        2.0       Xttrium    Part D    Germaben II-E       0.123     Sutton    ______________________________________

Manufacturing Procedure

Add water to mixing tank. Disperse PVP-K into water until completelydissolved. Next, disperse the Natrosol with good agitation untilcompletely hydrated and solution is clear and free of foreign matter.Add remaining ingredients in part A and mix batch while heating to75-80° C. Pre-blend ingredients in part B in separate vessel and heat to75-80° C. Add part B to part A and mix while cooling to 40° C. Pre-blendpart C and add to batch. Continue to mix while cooling to 35° C. Addpart D and mix completely. If necessary, adjust pH to 6.5-7.0.

EXAMPLE 2

    ______________________________________    Ingredient          Percent   Supplier    ______________________________________    Part A    Deionized Water     85.56     --    PVPK-30             1.00      ISP    Natrosol 250 HHR    0.78      Aqualon    Glycerin USP        2.90      Dow    Aloe Vera Powder 200XXX                        0.01      Tri-K    Part B    Crodacol C-95       0.80      Croda    Lipomulse 165       4.25      Lipo    Lexol IPM           0.60      Inolex    Vitamin E Acetate   0.10      Roche    Part C    Deionized Water     2.00      --    Chlorhexidine Gluconate 20%                        1.00      Xttrium    Part D    Germnaben II-E      1.00      Sutton    ______________________________________

Manufacturing Procedure

Add water to mixing tank. Disperse PVP K-30 into water until completelydissolved. Next, disperse the Natrosol with good agitation untilcompletely hydrated and solution is clear and free of foreign matter.Add remaining ingredients in part A and mix batch while heating to75-80° C. Pre-blend ingredients in part B in separate vessel and heat to75-80° C. Add part B to part A and mix while cooling to 40° C. Pre-blendpart C and add to batch. Continue to mix while cooling to 35° C. Addpart D to mix completely. If necessary, adjust pH to 6.5-7.0.

EXAMPLE 3

    ______________________________________    Ingredient           Percent   Supplier    ______________________________________    Part A    Deionized Water      86.58     --    Versene XL 100       0.02      Dow    (to pH = 8.0-9.0)    PVP K-30             0.85      ISP    Natrosol 250 HHR     0.70      Aqualon    Glycerin USP         2.00      Dow    Part B    Crodacol C-95        1.20      Croda    Lipomulse 165        4.25      Lipo    Lexol IPM            0.50      Inolex    Vitamin E Acetate    0.10      Roche    Irgasan DP300        0.50      Ciba-Geigy    Dow Corning 200 Fluid (350 cps)                         1.70      Dow                                   Corning    Carsonon N-9         0.50      Lonza    Part C    Germaben II-E        1.00      Sutton    ______________________________________

Manufacturing Procedure

Add water to mixing tank and adjust pH. Disperse PVP into water withgood agitation and mix until completely dissolved. Sift Natrosol intobatch and mix until completely clear and free of particles. Addremaining ingredients in part A and mix batch while heating to 75-80° C.Pre-blend ingredients in part B in separate vessel and heat to 75-80° C.Add part B to part A and continue mixing batch while cooling to 40° C.Add part C to batch and mix completely. Continue to mix while cooling to35° C.

EXAMPLE 4

    ______________________________________    Ingredient          Percent  Supplier    ______________________________________    Part A    Deionized Water     81.51    --    Carbopol 980        0.10     B. F. Goodrich    GIycerin USP        2.00     Dow    Versene NA2         0.05     Dow    Part B    Lipomulse 165       5.00     Lipo    Liponate SPS        1.00     Lipo    Emersol 132         1.50     Wilchem    Carsonon N-9 anti viral                        0.50     Lonza    Lexol IPM           0.50     Inolex    Dow Corning 200 Fluid (350 cps)                        1.20     Dow Corning    Vitamin E Acetate   0.10     Roche    Irgasan DP300       0.30     Ciba-Geigy    Part C    Deionized Water     1.00     --    Triethanolamine 99% 0.34     Union Carbide    Part D    Germaben II-E       1.00     Sutton    Fragrance #081411-393R                        0.30     Belmay    Glydant             0.30     Lonza    Part E    Deionized Water     3.00     --    PVP K-30            0.30     ISP    ______________________________________

Manufacturing Procedure

Add water to mixing tank. Disperse Carbopol into water with goodagitation and mix until completely dissolved. Add remaining ingredientsin part A and mix batch while heating to 75-80° C. Pre-blend ingredientsin part B in separate vessel and heat to 75-80° C. Add part B to part Aand continue mixing. Pre-blend part C and add to batch. Continue mixingbatch and being cooling to 40° C. Add part D to batch in order shown andmix completely. Pre-blend part E with good agitation. Mix untilcompletely clear and free of particles and add to batch. Continue to mixwhile cooling to 35° C. If necessary, adjust pH to 6.5-7.0.

EXPERIMENTAL RESULTS

Experiment No. 1

In this experiment, lotion of the formula given in example 3 above wasapplied to excised skin samples and challenged with pure cultures of E.coli, Salmonella and Staphylococcus aureus. Each sample was challengedwith liquid broth containing over 10⁷ organisms per millimeter.Microbial challenge was made four hours after the lotion was applied.Impressions of the skin onto blood agar plates were done in as little asfive seconds and up to five minutes after bacterial contact on the skin.Control samples were challenged without lotions. Results were based onvisual evaluation of the blood agar plates after the impressions hadbeen made by the skin samples and after at least twelve hours ofincubation at 37° C. A visual evaluation scale is described below.

Method

Fresh biopsied skin from baby pigs that had recently died from naturalcauses were prepared for the study by excision of the dermal andepidermal layers. Excised skin was shaved with a straight-edge razor toprepare a smooth epidermal layer. Sections approximately 3 cm×3 cm werekept in saline at 4° C. until used. The samples were washed with soapand water and rinsed in isopropyl alcohol but were not disinfected withanything that may have a residual effect. In each study control skinsamples, without lotion applied, were compared to the treated samples.The treated samples were prepared by rubbing a small amount of lotiononto the surface and rubbing it into the skin. Excess lotion was removedwith a clean towel and each sample was put in a 30° C. chamber tosimulate the temperature of the hands for a period of four hours. Thelarger section was cut into small squares approximately 0.5 cm to 0.5 cmprior to bacterial challenge.

Each sample was challenged by coating the sample with 2 drops of freshlyvortexed (mixed) broth culture of one of the three pathogens containingat least 10⁷ organisms per ml. At the appropriate time interval the skinwas pressed five times onto a blood agar plate in different spots todetermine the number of viable organisms that could be transferred tothe culture plates. The plate was then incubated at 37° C. for at least12 hours. Growth on the agar plate was scored according to the followingscale: 0=no growth, 1=slight growth, 2=moderate growth, 3=heavy growth,4=very heavy growth.

Contact time of the organisms on the treated and untreated skin was 5minutes, 2 minutes, 1 minute, 30 seconds or 0-25 seconds. The 0-25second sample was made blotting a skin sample and pressing it to theplate as soon as possible. The first impression to the plate wasapproximately 5 seconds after challenge. The sample was then held for 5seconds and another impression was made. This was repeated, givingimpressions made at 5, 10, 15, 20 and 25 seconds. The 5 second intervalimpressions were made to show the near-immediate antibacterial effect.

Results

With each organism the score for the control was a 4 (very heavygrowth). Significant reduction in organism numbers were seen on thetreated samples 4 hours after the lotion was applied and within 5seconds of contact time. Average scores for each organism type and eachtime interval are shown in Table 1. There was little difference ineffectiveness at the different time intervals. The inhibitionessentially the same at a few seconds as it was at 5 minutes.

                  TABLE 1    ______________________________________    Average Bacterial Growth Values (Scored 0-4) of 16 Replicates              Time      Control Bio-Safe Treated    ______________________________________    E. coli(10.sup.8)                5 minutes   4.0     1.19                2 minutes   4.0     0.94                1 minute    4.0     0.87                30 seconds  4.0     0.44                0-25 seconds                            4.0     0.81    Salmonella(10.sup.7)                5 minutes   4.0     0.31                2 minutes   4.0     0.69                1 minute    4.0     0.25                30 seconds  4.0     0.31                0-25 seconds                            4.0     0.25    S. aureus(10.sup.7)                5 minutes   4.0     0.12                2 minutes   4.0     0.19                lminute     4.0     0.19                30 seconds  4.0     0.06                0-25 seconds                            4.0     0.25    ______________________________________

The average scores for all organisms fell somewhere between no growthand the slight category. In this experiment, Bio-Safe® AntibacterialLotion was effective in significantly reducing the number of pathogenicorganisms on the skin when the microbial challenge was four hours afterapplication of the lotion and even if the contact time with treated skinwas only a few seconds. The challenge numbers, i.e., microbial quantity,used in this experiment greatly exceeds typical naturally occurringchallenge numbers. The results of this experiment demonstrate that thelotion composition is capable of broad spectrum bactericidal activitywithin seconds of contact and that the lotion maintains itsantibacterial efficacy for up to at least four hours after the lotion isapplied to the skin.

Experiment No. 2

This experiment was performed to determine the efficacy of the presentinvention as a teatdip for cows. Sixteen cows, Holsteins and Jerseys,completed the study. A formula similar to the examples provided abovewas used in the experiment. The lotion was approximately 90-percentdeionized water and included PVP, HEC, stearic acid, vitamin E, aloevera and triclosan. The condition of each cow's teats was examined anddescribed prior to treatment with the lotion. Teats were then dipped inthe lotion on a daily basis for one week. Then, teat condition wasexamined and described again. The results are reported below in Table 2.

                  TABLE 2    ______________________________________    Skin Condition Before and After One-Week    Application of Skin Barrier Treat Dip           Pre-                 Post-           Trial  Pre-Trial     Trial                                     Post-Trial    Cow #  Score  Comments      Score                                     Comments    ______________________________________    Holsteins    231    3      dry, flowered ends                                1    smooth, soft    364    2      slight flower LR                                1    smooth, soft flower    372    4      dry, rough, deep                                1    smooth, flowers                  cracks, flowered   present but shallow,                                     soft, healing    416    3      damaged sphincter                                1    smooth, soft    420    3      cracked teat end                                1    smooth    438    2      smooth, small 1    smooth, soft                  abrasion RR    366    3      all flowered at                                2    soft flowering                  sphincter    352    3      damaged teat ends,                                2    healing flowered ends                  flowered    407    1      smooth        1    smooth, soft    428    3      dry, not chapped                                1    smooth, soft    392    1      smooth        1    smooth, soft    472    3      mild dryness  1    smooth, soft    Jerseys    993    3      slight cracking of ends                                1    smooth    748    3      abrasion, RF  2    soft, rough on abrasion    754    3      cracks RR     2    soft cracks    991    1      smooth, slight                                1    smooth, soft                  teat end damage    ______________________________________

Experiment No. 3

The purpose of this experiment was to assess the skin sensitizationpotential of lotion according to the formula above given in example 2when applied topically to the skin of healthy human subjects.

The sensitization potential of the lotion was tested on 55 subjects (11males and 44 females). Testing was done in accordance with a modifiedDraize assay employing an 8 millimeter Finn Chamber (occlusive patch).

For the induction phase the product was applied to the scapular backMonday, Wednesday and Friday of each week for three consecutive weeks,with a final patch on Monday of the fourth week, for a total of eightapplications. Scoring of the skin sites was made at the end of each 48hour patch period (72 hours on weekends). The final reading was made onWednesday of the fourth week. Following a twelve day rest period, eachsubject received a single 48 hour occlusive challenge patch of theproduct on a naive skin site on the scapular back. Scoring of thechallenge site was made after removal of the patch and again two dayslater. The following scale was made for scoring:

0=No reaction (negative reading)

1=Erythema throughout the entire patch area

2=Erythema and edema

3=Erythema, edema and vesicles

4=Erythema, edema and bullae

Thirty-one subjects patched with the lotion showed a total of 98 1+reactions and 9 2+ reactions during the induction phase. Two subjectsalso presented a 1+ reaction at the 48 hour challenge reading. Since 1+reaction are minimal irritant responses and the 2+ reactions resolvedspontaneously, the lotion is judged to be neither a significant irritantnor contact sensitizor.

Experiment No. 4

This experiment was performed to challenge the stability of the lotionformula given above in example 3. The test was performed by BioScreen®Testing Services, Inc. in Torrance, Calif. The test was referred to asU.S.P. Challenge Test with Rechallenge on Day 12. BTS test method M101from reference U.S.P. 23 was used. The following organisms: Aspergillusniger, Candida albicans, Escherichia coli, Pseudomonas aeruginosa,Staphylococcus aureus, were used to challenge the specimen for 28 daysat intervals of 7, 14, 21 and 28 days. The product was rechallenged atday 12 with the same organisms.

The results of the experiment are reported below in Table 3.

                  TABLE 3    ______________________________________              Initial    Micro     Inocu-   Day 7    Day 14                                      Day 21 Day 28    Organism  lum/ml   Colony Forming Units/ml    ______________________________________    A. niger  5.2 × 10.sup.5                       <10      <10   <10    <10    C. albicans              5.5 × 10.sup.5                       <10      <10   <10    <10    E. Coli   9.3 × 10.sup.5                       <10      <10   <10    <10    P. aeruginosa              7.7 × 10.sup.5                       <10      <10   <10    <10    S. aureus 8.0 × 10.sup.5                       <10      <10   <10    <10    ______________________________________

The preservative is effective if: (a) the concentration of viablebacteria is reduced to not more than 0.1-percent of the initialconcentration by day 14, (b) the concentration of viable yeasts andmolds remains at or below the initial concentration during the first 14days, and (c) the concentration of each test microorganism remains at orbelow these designated levels during the remainder of the 28 day testperiod.

The data reported in Table 3 shows that preservative was stable andeffective for the organisms Aspergillus niger, Candida albicans,Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus.Based on this experiment we can predict that the lotion of the presentinvention will have a stable shelf life for at least about 2 years.

Experiment No. 5

This experiment was performed by the test tube dilution method todetermine the lowest concentration of test product that will inhibitbacterial growth. This concentration is referred to as the minimuminhibitory concentration (MIC). The test was done by performing 2-foldcereal dilutions of the test product in broth (1:2 through 1:256) andinoculating the dilutions separately with the test organisms. Theconcentration of the test product in the last tube that exhibitinhibition (no growth) is reported as the MIC. The test product thatshows no inhibition of bacterial growth (growth in all tubes) isreported as "failed."

The lotion was challenged with the following microorganisms: Escherichiacoli (EC), Enterbacter aerogenes (EA), Pseudomonas aeruginosa (PA),Klebsiella pneumoniae (KP), Micrococcus luteus (ML), Proteus mirabilis(PM), Serratia marcescens (SM), Staphylococcus aureus (SA) andStreptococcus bovis (SB). The results are reported in Tables 4 and 5below.

                  TABLE 4    ______________________________________    Organism  E.A.      E.C.      K.P.    M.L.    ______________________________________    Undilute  -         -         -       -    1:2       +         +         +       +    1:4       +         +         +       +    1:8       +         +         +       +    1:16      +         +         +       +    1:32      +         +         +       +    1:64      +         +         +       +    1:128     +         +         +       +    1:256     +         +         +       +    Positive control              +         +         +       +    MIC       Undilute  Undilute  Undilute                                          Undilute    ______________________________________     (+) = Growth (-) = Growth

                  TABLE 5    ______________________________________    Organism    P.M.     P.A.    S.M.   S.A.  S.B.    ______________________________________    Undilute    -        -       -      -     -    1:2         +        -       +      -     -    1:4         +        +       +      +     +    1:8         +        +       +      +     +    1:16        +        +       +      +     +    1:32        +        +       +      +     +    1:64        +        +       +      +     +    1:128       +        +       +      +     +    1:256       +        +       +      +     +    Positive control                +        +       +      +     +    MIC         Undilute 1:2     Undilute                                        1:2   1:2    ______________________________________     (+) = Growth (-) = Growth

The results show that the lotion is effective against all the bacteriaused in the study even when diluted to 1:256.

Experiment No. 6

This experiment was performed to determine whether lotion of the presentinvention is orally toxic. Again, lotion of the formula set forth inexample 3 above was used in the experiment.

Healthy, young adult Wistar derived albino rats weighing about 150 to300 grams were obtained from ACE Animals, Inc., Boyertown, Pa. Five maleand five female rats were selected for the dose level chosen for thisstudy.

The rats were fed Purina Rat Chow. Feed and water were suppliedad-libitum. Animals were fasted 18-24 hours prior to dosing. Feed andwater were returned ad-libitum immediately thereafter.

Prior to the test period the animals were each uniquely identified withsequentially numbered ear tags and individually housed in wire bottomcages in a temperature controlled room with a 12 hour light/dark cycle.Feed and water were provided ad-libitum after dosing.

During the fast period water was allowed ad-libitum. After fasting ratswere individually weighed. All body weights were recorded and individualdoses calculated based on these weights. The test material was thendelivered by gavage at a dose level of 5.0 g/kg body weight. Once thematerial had been ingested completely, feed and water were providedad-libitum. The rats were individually caged and observed for mortalityor other signs of gross toxicity for 14 days. At the end of the testperiod, all surviving animals were weighed. Results of the experimentare reported below in Table 6.

                                      TABLE 6    __________________________________________________________________________             Body Weight              Mortality    Animal #          Sex             Initial                 Final                     Dosage (g)                           Dose Delivered* (ml)                                      Day                                         Autopsy    __________________________________________________________________________    2967  M  230 289 l.15  1.16       NA NA    2968  M  241 299 1.21  1.22       NA NA    2969  M  175 239 0.88  0.89       NA NA    2970  M  276 300 1.38  1.39       NA NA    2971  M  250 276 1.25  1.26       NA NA    x        234 281 1.17  1.18    2854  F  293 293 1.47  1.48       NA NA    2855  F  250 244 1.25  1.26       NA NA    2856  F  259 272 1.30  1.31       NA NA    2859  F  293 293 1.47  1.48       NA NA    x        270 272 1.36  1.37    __________________________________________________________________________     *1 ml weights 0.9971 g     NA -- Not applicable

The results show that the lotion of the present invention is orallynon-toxic.

We claim:
 1. An antibacterial lotion comprising:a polymer mixturecomprising polyvinylpyrrolidone and hydroxyethylcellulose in an aqueoussolution, an antibacterial agent comprising2,4,4'-trichloro-2'-hydroxydiphenylether or chlorhexidine gluconate, andan emulsification system comprising a mixture of glyceryl stearate andpolyethylene glycol.
 2. The composition of claim 1 wherein thepolyvinylpyrrolidone has a molecular weight in the range of20,000-40,000 daltons and is provided in the solution at a concentrationof between approximately 0.10 to 2.00 percent (w/w).
 3. The compositionof claim 1 wherein the hydroxyethylcellulose is provided in the solutionat a concentration of between approximately 0.10 to 2.00 percent (w/w).4. The composition of claim 1 wherein the antibacterial agent is2,4,4'-trichloro-2'-hydroxydiphenylether ("triclosan").
 5. Thecomposition of claim 4 wherein the triclosan is provided in an aqueoussolution at a concentration of between about 0.10 to 2.00 percent (w/w).6. The composition of claim 1 wherein the antibacterial agent ischlorhexidine gluconate.
 7. The composition of claim 6 wherein thechlorhexidine gluconate is provided in the aqueous solution at aconcentration of between about 0.10 to 3.00 percent (w/w).
 8. Thecomposition of claim 1 wherein the emulsification system comprisesLipomulse 165 at a concentration of between approximately 0.50 to 5.00percent (w/w).
 9. The composition of claim 1 further comprising anemulsion stabilizer.
 10. The composition of claim 9 wherein the emulsionstabilizer is Crodacol C-95 at a concentration of approximately 0.10 to2.00 percent (w/w).
 11. A lotion for topical application on skincomprising:a polymer mixture in an aqueous solution which dries on skinto form a penetrant barrier for up to several hours after application,an antibacterial agent dispersed in the solution which is effective forat least about four hours after application on skin to kill a broadspectrum of bacteria which come into contact with the agent, and anemulsifying system comprising a mixture of glyceryl stearate andpolyethylene glycol as an emulsifier, and cetyl alcohol as an emulsionstabilizer.
 12. The lotion of claim 11 wherein the polymer mixturecomprises polyvinylpyrrolidone and hydroxyethylcellulose.
 13. The lotionof claim 11 wherein the antibacterial agent is either triclosan orchlorhexidine gluconate.
 14. The lotion of claim 11 further comprisingan antiviral agent.
 15. The lotion of claim 14 wherein the antiviralagent comprises nonylphenol thoxylate.
 16. The lotion of claim 11wherein the polymer mixture comprises an acrylic polymer.
 17. The lotionof claim 9, wherein the emulsion stabilizer comprises cetyl alcohol. 18.The lotion of claim 1 further comprising a plasticizer comprising amyristic acid ester.
 19. An antibacterial lotion comprising:a polymermixture including polyvinylpyrrolidone and hydroxyethylcellulose in anaqueous solution, an antibacterial agent comprising2,4,4'-trichloro-2'-hydroxydiphenylether or chlorhexidine gluconate, andan emulsification system comprising an emulsifier including a mixture ofglyceryl stearate and polyethylene glycol at a concentration of betweenapproximately 0.50 to 5.00 percent (w/w), and an emulsion stabilizercomprising stearyl alcohol at a concentration of approximately 0.10 to2.00 percent (w/w).
 20. The lotion of claim 19 further comprising aplasticizer comprising a myristic acid ester.